Agent for the purification of oils



Patented Apr. 30, 1935 1,999,335

rrso STATES PATENT OFFICE AGENT FOR THE PURIFICATION OF OILS Percival John McDermott, Manchester, England,

assignor to Refiners Limited, Manchester, England, a British company No Drawing. Application February 13, 1933, Serial No. 656,583

' 4 Claims. (01. 252-1) This invention relates to the purification of mixing continued for 15-20 minutes. The mapetrol and like oils and spirits by the removal terial is then dried at 110 C. and ground to pass therefrom of sulphurous, resinous and other una 60 mesh screen. In the description this reagent desirable impurities and by the polymerization of will be referred to as base reagent and it mustbe undesirable unsaturated hydrocarbons in such understood that the proportions and screen size 5 a way that desirable unsaturated hydrocarbons can be materially varied without departing from are not affected and therefore obtaining increased the spirit and scope of the invention. Variations yields. will depend on the raw materials used; for ex- The invention is a further modification and imample, the solubility of the iron oxide, the ratio provement of reagents and processes heretofore of ferric and'ferrous oxide in the iron oxide, the 10 described in prior Patents 1,658,285 and 1,742,343. lime or other alkali in the fullers earth, etc. This The v ry h b en made that when treating base reagent is substantially that which has been crackedgasolines and especially those crude disfound very suitable for the purification of benzols tillates obtained from vapor phase cracking procand. coal tar naphthas.

l5 esses, the best results are obtained when using To make one type of reagent used in this work, certain ratios of ingredients in the treating re- 360 parts of the-base reagent is mixed with 360 a ent. This rea nt c nsist -of what i termed parts of fullers earth and 270 parts of 96% sulhel'ein an acid ferric Sulphate, being e mixture phuric acid. This is denoted as reagent I in this or combination of ferric sulphateand free sulspecification,

0 phuric acid, mixed with an absorbent earth such An ther type is prepared by mixing 830 parts of as fullers earth. Y the base with 175 parts of the 96% sulphuric acid.

In general, the Spirits to b treated are This is referred to as reagent II. This further t t d w t th a nt t a vat d t mp atur addition of acid sometimes increases the soluble al y a v taking P p precautions iron with certain types of iron oxides.

o avoid ap losses, then removing the Spent When these reagents were analyzed as far as 25 r a nt by filtration or other suitable m a new the water soluble constituents are concerned, the tralizing with alkali and steam distilling. The following results were obtained:-

I ratio of free sulphuric acid to ferric sulphate in the reagent is maintained at a higher point than Base Mmmei Mixt r 11 was satisfactory for the treatment of benzols and coal tar naphthas and has resulted in quite sur- Free sulphuric acid Percent Percent Percent prising results when these modified reagents were ,5 4 0 1e 5 applied to. the cracked distillates of petroleum. 33233; 5g 5g gg% f;3 t} 1% The process can be carried out in various ways depending on the typeof refined product deslred The above analyses were made by boiling a Pop 35 and the crude to be treated.

The invention will be illustrated by the following examples but it is not intended that the scope shall be limited thereby as the proportions, tem- 40 peratures, etc. may be varied over quite wide limits from those given in the specific examples.

In preparing the various reagents, it is contion of the finished reagent with water, filtering and making the tests. on the filtrate. Free acid is determined by. titrating in the presence of potassium fluoride. The total iron is obtained by titration with potassium permanganate after treatment with stannous chloride and mercuric venient to prepare a base mixture along the fol- F The.fenus 93 obtamed by f lowing lines: 400 parts by weight of iron oxide, tltmtlQn wlthwt reducmg agents fernc preferably a material such as is obtained as the bemg obtamed by dlfierence- 45 by-product of aniline manufacture or a calcined In gBnQPTaL the reagents used most successfully spent gas oxide is mixed in a dough mixer with 80 for treatmg Petroleum hydmcfarbons and 9 parts of fullers earth. To the mix is added 630 oially crude gasoline e aratlo of r p unc parts of 82% sulphuric acid and. mixing continc d to ferric sulphate in excess of 0.35 and the I ued until the pasty mass first formed become a best results have been obtained when this ratio 50 fairly dry powder which usually contains some has been between 0.45 and 0.80 although in some lumps. After breaking up these lumps, 210 parts cases satisfactory results have been obtained morefullersearth are added and mixed in. Final- ,when the ratio has been above 1.00. When the 1y, 210 parts of 82% sulphuric acid and a small ratio of acid to ferric sulphate is varied, it is someamount of nitric acid (520 parts) are added and times-necessary to vary the proportions of the absorbent earth so as to maintain the characteristics necessary for convenient application of the reagent. The fullers earth can bereplaced by other suitable absorbent materials.

The reagents are regarded for the purpose of defining them in the claims as mixtures of absorbent earth and acid ferric sulphate with varying ratios of free sulphuric acid (H2804) and ferric sulphate (E62 (S04) 3) In the use of these reagents, taking for example reagent I, a crude distillate from the vapor phase cracking of petroleum was employed. This crude distillate on assay contained about of 437 F. end point gasoline and had been given a wash with strong caustic soda solution. -It was distilled and cut at 300 F., treating the distillate and residue separately. The light distillate was treated with 30% of the total reagent used, mixing for 40 minutes at a temperature of 50 C. The residue was mixed with 70% of the total reagent at 60 C. for 45 minutes. Both were then filtered, recombined and steam distilled, the distillate being neutralized with ammonia or caustic soda solution. The total use of reagent corresponded to 6 /2 pounds per barrel (42 United States gallons)' of crude treated.

The product obtained showed that of the 437 end point gasoline present in the original crude, 95.5% were recovered in the refined distillate. The refined distillate cut to 437 Saybolt colour of 20, milligrams it at the same or higher Either this method or the one firstdescribed can be carried out either as a batch or continuous process.

A still further method of treatment may be descri ed as follows:A similar crude vapor phase cracked distillate after caustic soda washing wasmixed with 5 pounds of reagent II (per barrel). The mixing was carried on at 170 .F. and continued for 2% hours. The product was filtered, neutralized with caustic soda, and distilled to give a product of 435 F. end point. The yield obtained was 93.5% of that originally in the crude, the polymerization loss being only 6.5%.

The product was of very high' grade with a color of 27-28 Saybolt, glass dish gum of 2 milligrams per c. c., 49% by volume of aromatics and unsaturates, a bromine number of 96 and a C. F. R. research method octane number of 81. On exposure to light and air, a. good degree of color and gum stability was noted. The treatment as above described can be carried out either in batches or continuously.

The process removes the impurities, causing color and gum formation, without destroying the valuable unsaturated hydrocarbons in gasoline. In this way, yields are increased and anti-knock values preserved.

Although the process has been described in connection with vapor phase cracked gasolines which contain a very high proportion of unsaturated hydrocarbons, it can be utilized to advantage on crude distillates of other types of cracking processes oron straight run crudes from topping or similar operations.

What I claim is:

1. A new composition of matter consisting of a solid substantially dry powdered or granular material comprising an adsorbent earth and a mixture of ferric sulphate and free sulphuric acid adsorbed'thereon, the ratio of the free sulphuric acid to the ferric sulphate exceeding 0.35 but not exceeding 0.80.

2. A new composition of matter consisting of a solid substantially dry powdered or granular material comprising an adsorbent earth and a mixture of ferric sulphate and free sulphuric acid adsorbed thereon, the, ratio of the free sulphuric acid to the ferric sulphate exceeding 0.45 but not exceeding 0.80.

3. A composition of matter as claimed in claim 1 wherein the adsorbent earth is fullers earth.

4. A new composition of matter consisting of a solid substantially dry powdered or granular material comprising fullers earth and a mixture of ferric sulphate and free sulphuric acid adsorbed thereon, the ratio of the free sulphuric acid to the ferric sulphate exceeding 0.45 but not exceeding 0.80.

PERCIVAL JOHN M'cDERMO'I'I'. 

